Increase timeout for getting to login prompt in QEMU

Testing has shown that it can take a little more then
two minutes at times to get to the login prompt and
successfully login. Increase default timeout and make
it configurable.

Change-Id: Ibe86e2b214cdedf7378da8920e76526cf294127b
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
1 file changed